The present invention relates to the processing of semiconductor wafers in plural chambers. As shown in our commonly assigned U.S. Pat. No. 4,715,921, issued Dec. 29, 1987 and U.S. Pat. Applications Ser. No. 853,775, Filed Apr. 18, 1986, and Ser. No. 115,774, Filed Oct. 30, 1987, the use of plural chambers to process semiconductor wafers permits more efficient, rapid and flexible semiconductor wafer plasma environment processing. In that disclosure the ability is provided to address the wafers in an individual cassette to different ones or multiples of processing chambers associated with that one cassette.
In the use of multiple chambers it can occur that one or more chambers must be serviced. Time is lost in the process of repairing or converting those chambers to other functions due to the extended period of time needed to bring chambers to the vacuum state needed to process semiconductor wafers.